1. Field of the Invention
This invention relates to a process for producing phenyl chlorothioformates. Phenyl chlorothioformates are very useful as intermediates for drugs and agricultural chemicals.
2. Description of Prior Art
It is known that phenyl chlorothioformates can be produced by reacting a phenol compound with thiophosgene in the presence of a dehydrohalogenating agent. However, since thiophosgene has a high toxicity, its handling requires great care. In view of the risk of such accidents as leakage, it is desirable to avoid the storage or transfer of thiophosgene in large quantity. Hence, the present inventors previously proposed a process for producing phenyl chlorothioformates by allowing sulfur dioxide to react with a mixed solution consisting of a phenol compound, perchloromethyl mercaptan, an organic solvent and water and then adding a dehydrohalogenating agent thereto. In this process, however, a phenoxydichloromethanesulfenyl chloride is formed as a by-product, whereby the yield of phenyl chlorothioformates is reduced.